The present invention relates to a decentralized control system in which a plurality of control processors and a plurality of devices are connected to a network.
In a conventional decentralized control system of the prior art, a plurality of controllers are connected to a network and each controller is linked with devices as control objective units. In the system, each controller is individually provided with programs, and programmers create programs in consideration of the relationship of connections respectively between the controllers and the devices. Additionally, it is required that each program includes description of processing to control each device as well as description of synchronization processes between the controllers to control sequence in the overall system. This consequently leads to a problem that the program description becomes complex.
Moreover, when the devices are fixedly connected to each associated controller and the contents of the program of the controller are also fixed, the program of each controller is required to be modified each time the connecting relationship between the controller and the devices is altered. There consequently arises a program that the program modification requires an increased number of steps and the program cannot flexibly cope with changes of the system configuration.
JP-A-10-177495 discloses a decentralized control system, which is known as an example of the decentralized control system connected to a network as above. In the known example, there has been described a method in which a computer as a server converts a program uniformly described in one standard programming language into programs to be executed respectively by a plurality of microcomputers connected to the network and delivers the converted programs to the respective microcomputers.